1. Field of the Invention
This invention relates to new and improved sampling apparatus and method which are capable of automated sampling from both closed and open sample tubes attendant sample analysis.
2. Description of the Prior Art
Although a number of closed tube samplers are known in the prior art, most relevantly in this instance the closed tube sampler included in the hematology instrument as marketed by Coulter Electronics, Inc., Hialeah, Florida as the Coulter "S-PLUS VI," and the closed tube sampler included in the hematology instrument as marketed by Cortex Research Corporation, Northbrook, Illinois under the Trademark "Double Helix;" it may be understood that neither of these prior art closed tube samplers is configured or operable in the manner of the novel sampler of this invention to provide for versatility of application in terms of the immediately available option of automatically switching between closed and open tube sampling through use of simple selector valve means and essentially the same sample supply means without requirement for external modification in sampler configuration; to provide for simplicity of configuration and operation in terms of utilizing essentially the same flow paths for sample supply and for inter-sample sampler rinsing; or to provide for significantly increased sample analysis accuracy in terms of insuring the consistent supply of precisely determined and readily reproducible sample volumes attendant repeated sampling from the same closed sample tube, and in terms of the absolute minimization of sample carryover to levels below those of clinical significance.
Too, and although a particularly wide variety of open tube samplers are known in the prior art, most relevantly in this instance the open tube samplers as disclosed in U.S. Pat. Nos. 3,719,086, 3,756,459, 3,759,667, 3,912,452 and 4,065,973, it may be understood that none of these prior art open tube samplers is configured or operable in the manner of the novel sampler of this invention to provide for versatility of application in terms of the immediately available option of switching from open to closed tube sampling; to provide for simplicity of configuration in terms of utilizing essentially the same flow paths for sample supply and for inter-sample sampler rinsing; or to provide for significantly increased sample analysis accuracy in terms of the absolute minimization of sample carryover to levels below those of clinical significance for both open and closed tube sampling.